(a) Field
The present disclosure relates to an apparatus for predicting a fault state of an inverter, and particularly, to an apparatus and a method for predicting a fault state of an inverter, which can pre-diagnose a fault state of a switching element included in the inverter based on an output signal output from the inverter.
(b) Description of the Related Art
In recent years, in vehicles using a combustion type engine, other types of vehicles which are environment-friendly and consider fuel efficiency, that is, a hybrid vehicle or an electric vehicle have been actively researched and developed.
In the hybrid vehicle, the existing engine and a driving motor driven with electric energy are associated with each other to drive the vehicle with two driving sources. The electric vehicle is driven only by a driving motor driven with the electric energy. The vehicles have held the prominent position as realistic alternative next-generation vehicles which have come into the spotlight worldwide due to an effect of improvement of fuel efficiency together with reduction of environmental pollution by exhaust gas.
The vehicles include an inverter for controlling the driving motor.
The inverter switches DC power by using a switching element and converts and outputs the DC power into AC power. The inverter controls a switching time of the switching element to control the driving motor.
The switching element used for the inverter adopts a transistor, a metal oxide silicon field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and the like. However, the transistors have a disadvantage in that a circuit configuration is complicated and an operation speed is low instead of a low price and the MOSFET has a disadvantage in that efficiency decreases in high voltage instead of a high operation speed. As a result, since the IGBT has advantages of the transistor and the MOSFET, the IGBT has been recently used a lot.
In the related art, since a deterioration state of the switching element cannot be pre-diagnosed and the deterioration state can be sensed after a fault occurs, a problem occurs, in which the vehicle cannot be driven in the worst case.
The disclosure of this section is to provide background of the invention. Applicant notes that this section may contain information available before this application. However, by providing this section, Applicant does not admit that any information contained in this section constitutes prior art.